A versatile organocatalyst for the asymmetric conjugate addition of nitroalkanes to enones
作者:Claire E. T. Mitchell、Stacey E. Brenner、Steven V. Ley
DOI:10.1039/b511441a
日期:——
5-Pyrrolidin-2-yltetrazole performs as an improved catalyst for the asymmetricaddition of a range of nitroalkanes to cyclic and acyclic enones, with good to excellent enantioselectivity.
An efficient, asymmetric organocatalyst-mediated conjugate addition of nitroalkanes to unsaturated cyclic and acyclic ketones
作者:Claire E. T. Mitchell、Stacey E. Brenner、Jorge García-Fortanet、Steven V. Ley
DOI:10.1039/b601877g
日期:——
5-Pyrrolidin-2-yltetrazole is a versatile organocatalyst for the asymmetric conjugateaddition of nitroalkanes to enones. Using this catalyst, this transformation requires short reaction times, tolerates a broad substrate scope, and possibly proceeds via generation of an iminium species.
Asymmetric multifunctional organocatalytic Michael addition of nitroalkanes to α,β-unsaturated ketones
作者:Pengfei Li、Yongcan Wang、Xinmiao Liang、Jinxing Ye
DOI:10.1039/b804540b
日期:——
Cinchona alkaloid derived primary amine thioureas organocatalyzed Michael addition of nitroalkanes to enones in good yield and up to 98% ee and offered a new way to construct quaternary stereocenters from enones and nitroalkanes.
A General, Scalable, Organocatalytic Nitro-Michael Addition to Enones: Enantioselective Access to All-Carbon Quaternary Stereocenters
作者:Xiaodong Gu、Yuanyuan Dai、Tingting Guo、Allegra Franchino、Darren J. Dixon、Jinxing Ye
DOI:10.1021/acs.orglett.5b00387
日期:2015.3.20
Michael addition of nitromethane to five-, six-, and seven-membered β-substituted cyclic enones with excellent enantioselectivity, offering scalable, asymmetric access to all-carbon quaternary stereocenters. The reaction scope can be expanded to include linear acyclic enones, and excellent levels of enantioselectivity are also observed. Furthermore, this organocatalytic, asymmetric nitro-Michael reaction
Chiral diethyl (2R)-tetrahydropyrro-2-ylphosphonate is an effective catalyst for the Michael addition of nitroalkanes to alpha,beta-unsaturated ketones. This Study revealed that the hydrate salt of this alpha-aminophosphonate was found to be a better catalytic species. Moderate to high enantioselectivities were achieved in reactions that tolerate various nitroalkanes and enones in the presence of low loading of both catalyst ( 10 mol %) and bulk base (25 mol %). (C) 2008 Published by Elsevier Ltd.